The invention relates to a mount for a measuring device, and in particular to a mount having a spring-loaded clamp for releasably attaching the mount to a flange.
In the manufacture of automobiles, as with many devices, it is important that the components thereof are properly aligned with one another for proper function. For example, the doors of a vehicle should be properly aligned with the body of the vehicle. An elastomeric door seal is fixed to the body of the vehicle about the door opening therein. The door seal is fixed to a door seal flange which extends inwardly into the door opening. The door presses against the door seal so that the door seal provides a leak-tight seal between the door and the body to keep wind and rain out of the passenger compartment of the vehicle. In order for the door seal to work, the door must be properly positioned relative to the door seal flange. The door must be close enough to the door seal flange to fully engage the door seal when the door is closed in order to provide a seal therewith. However, the door must not be positioned so close to the door seal flange that the door seal prevents the door from fully closing.
Thus, after the door is assembled to the body of the vehicle, it would be desirable to check for proper spacing between the door and the door seal flange. In a modem vehicle assembly plant, such measurements should be done expeditiously, so as not to slow production. One method which has been used in the past includes placing lumps of clay on the door seal flange to be compressed by the door when the door is shut. A measurement is taken of the thickness of the clay after the door is reopened. This measurement is difficult to do with accuracy and repeatability, and thus tends to be a relatively slow process.
Another method used in the past is to mount a metal housing to the door seal flange with a screw clamp such that a reference surface contacts the door seal flange. An arm is pivotally mounted on the housing in such a way that the arm experiences a fair amount of friction as it pivots, which tends to hold the arm in place. The arm is set up in a first position relative to the reference surface, and is moved to a second position by the door as it closes. After the door is re-opened, a probe transducer is fitted to the body to measure the distance between the second position of the arm and the reference surface. A device of this type is the 235 Door Seal Gap Gage, 234 Probe Adapter, and 200-SB probe transducer sold by LMI Corporation of Byron, Mich. A problem with this device is that the amount of friction between the pivoting arm and the housing is critical to the accuracy of the measurement. If the amount of friction is too high, the arm may hold the door further open than the closed position the door would move to without the resistance of the arm, thus causing an inaccurate reading. If the amount of friction is too low, the probe transducer may cause the arm to move when pressed against the arm. This problem is made worse by the fact that the amount of friction tends to change significantly as the device wears during use. Also, it is noted that installing this device is a two handed operation: one hand is needed to position the housing, and the other hand is needed to operate the screw clamp to clamp and unclamp the housing from the door seal flange.
Other known methods include measuring the gap between the door seal flange and the door with feeler gauges or calipers after the door is closed. These methods are unreliable due to the difficulty in accessing the space between the door seal flange and the door when the door is shut, and the degree of skill needed to obtain accurate, repeatable readings with such measuring instruments under such conditions.
Thus, it would be desirable to provide a mount for a measuring instrument that may be quickly and easily mounted on and removed from a part to be measured. It would also be desirable to provide a mount for a measuring instrument that ensures accurate measurements when the mount is moved to different locations on the part. It would further be desirable to provide a mount for a measuring instrument that provides flexibility in measuring differently oriented parts, and that provides a means to measure a part when the part is obstructed by another structure.